Five polymorphic
microsatellite loci were developed from genomic DNA of
red snapper (Lutjanus campechanus) and used to
evaluate genetic variation among 194 red snapper sampled
from three locations in the northern Gulf of Mexico and
one location off the northern Yucatan Peninsula.
From 5 to 13 alleles were observed per locus, and observed
heterozygosities ranged from 0.143 to 0.779. No
significant departures from exceptions of Hardy Weinberg
equilibrium were found at any locus either within samples
or when samples were pooled across localities. Locus-by-locus
test of allele-frequency homogeneity over the four localities
were non-significant. Weir and Cockerhams at each
locus ranged from -0.003 to 0.0012, and Statkins
RST at each locus ranged from -0.014 to 0.008. None of
the estimates of and RST differed significantly from zero,
and magnitudes of and RST did not appear to vary with
geographic distance between localities. These results
are consistent with the hypothesis that red snapper at
these localities comprise a single population. There are,
however, a number of caveats to this hypothesis. Detection
of population structure of red snapper in the Gulf may
require larger numbers of samples, and the importance
of importance of local reproduction to recruitment needs
to be examined via examination of larvae settling onto
reefs. There was a positive but non-significant correlation
between mean number of repeat units per microsatellite
allele and heterozygosity of the locus.